/*
 * Copyright 2014 The Netty Project
 *
 * The Netty Project licenses this file to you under the Apache License,
 * version 2.0 (the "License"); you may not use this file except in compliance
 * with the License. You may obtain a copy of the License at:
 *
 *   http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
 * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
 * License for the specific language governing permissions and limitations
 * under the License.
 */

package io.netty.resolver;

import io.netty.util.concurrent.EventExecutor;
import io.netty.util.concurrent.Promise;
import io.netty.util.internal.UnstableApi;
import java.net.SocketAddress;
import java.util.Collections;
import java.util.List;

/**
 * A {@link AddressResolver} that does not perform any resolution but always reports successful
 * resolution. This resolver is useful when name resolution is performed by a handler in a pipeline,
 * such as a proxy handler.
 */
@UnstableApi
public class NoopAddressResolver extends AbstractAddressResolver<SocketAddress> {

  public NoopAddressResolver(EventExecutor executor) {
    super(executor);
  }

  @Override
  protected boolean doIsResolved(SocketAddress address) {
    return true;
  }

  @Override
  protected void doResolve(SocketAddress unresolvedAddress, Promise<SocketAddress> promise)
      throws Exception {
    promise.setSuccess(unresolvedAddress);
  }

  @Override
  protected void doResolveAll(
      SocketAddress unresolvedAddress, Promise<List<SocketAddress>> promise) throws Exception {
    promise.setSuccess(Collections.singletonList(unresolvedAddress));
  }
}
